Patent · US Expired

Branched polycarbonate resin

US6222004A · kind A · utility

4Cited by
3References
4Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMay 26, 2000
Grant dateApr 24, 2001
Priority date
Expiry dateMay 26, 2020

Classification

  • Technology area (CPC C)Chemistry; Metallurgy
  • CPC primaryC08G64/14
  • WIPO fieldMacromolecular chemistry, polymers
  • WIPO sectorChemistry

Abstract

A tetrahydric phenol having a specific structure, such as .alpha.,.alpha.'-dimethyl-.alpha.,.alpha.,.alpha.',.alpha.'-tetrakis(4-hyd roxyphenyl)-p-xylene, is used as the branching agent in producing a branched polycarbonate resin. The resin has a branching agent content (branching agent/(dihydric phenol+chain terminator+branching agent).times.100) of from 0.01 to 0.4 mol %, and an intrinsic viscosity [.lambda.] of from 0.5 to 0.6, and is substantially free from crosslinks. The resin has such a reduced branching agent content and has good melt characteristics including high melt tension. It exhibits improved moldability in blow molding, etc., and gives good moldings especially having improved appearances and color tone.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.